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    <title>Document</title>
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    <div class="x-double-bounce1">

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    <style>
        .x-double-bounce1{
            background:green;
            width:40px;
            height:40px;
            border-radius: 20px;
            -webkit-animation: bounce 2.0s infinite ease-in-out;
            animation: bounce 2.0s infinite ease-in-out;
        }
    </style>
</body>
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